[jlefo7p6]

I think you were referring to the n-body problem (http://en.wikipedia.org/wiki/N-body_problem). If so, I suggest not neglecting gravity.

Without gravity (and either assuming these guys don't run into each other or can somehow pass through each other), the position of each body is independent, and can be found through the following equation:

Position = Initial + (Velocity * Time)

Blah blah vector components blah blah, but you get my point.

[ars]

He included "charge" which (mathematically) is identical to gravity.

Plus he said relativistic, so the very concept of "position" (and time) is not so simple.

[trjordan]

If you're assuming a fixed viewer, it's actually pretty easy to define position and time. There are just relativistic corrections to a bunch of the terms.

[ars]

Only if you assume no acceleration on the objects. But he said charge, so they do accelerate.

You'd have to figure out the position and velocity of each one relative to the others to figure would what the effect of the charge will be. And don't forget to include the propagation delay of the charge field.

This is by far not a simple problem. Much much harder than the N-body problem.

If the top poster had only left out "Physicists are ridiculous." it would have been quite an insightful post, instead it was an inciteful one.

Look up http://en.wikipedia.org/wiki/Einstein_field_equations - add in http://en.wikipedia.org/wiki/Stress-energy_tensor and you'll see that the motion of relativistic bodies is barely understood.

I'm upmoding him, because I think -7 is more than enough.